there's going to be people saying this is my old brother-in-law and he's no good. there's going to be a lot of false starts on it. look, if you're a person on that video and you're not a bomber, you should be calling the fbi and saying, hey, i'm just a witness. you have the wrong guy. i wouldn't count on that happening. if that was the case, you should be calling yourself and you would be a witness. there's going to be false positives but all the people that get identified, one of those people is going to be -- two of those people is going to be white hat and dark hat and then it's going to transpire. the local police will get involved, state troopers, the police around the world, intelligence agencies. >> and it goes on and on. don clark, you were head of fbi field operations. tonight what are they bracing for? i'm sure they are banking many calls. what is the call that you'd be hoping to get? >> well, the call that you would be hoping to get is that some good, faithful law enforcement agent happened to pick up a person with this description, whether it's in a car